The reference in this specification to any matter which is known, is not, and should not be taken as an acknowledgment or admission or any form of suggestion that that known matter forms part of the common general knowledge in the field of endeavour to which this specification relates.
Resveratrol and its derivatives, azelaic acid or a salt or ester thereof, and one or more of black cumin seed oil, chaulmoogra oil, magnolia bark extract and manuka oil possess a range of properties that are beneficial to the skin. For example, resveratrol and its derivatives possess antioxidant and anti-inflammatory properties and also promote collagen production. Azelaic acid or a salt or ester thereof acts to exfoliate the skin and also possesses antimicrobial properties. One or more of black cumin seed oil, chaulmoogra oil, magnolia bark extract and manuka oil possess anti-inflammatory and antibacterial properties when applied to the skin.
However, when these actives are applied to the skin in most formulations they only act for relatively short periods of time, and to provide beneficial effects for longer periods frequent application is required. Furthermore, the properties of these actives would also be beneficial to the dermis of the skin, but when applied to the skin in most formulations these actives have limited activity in the dermis.
Hyaluronate crosspolymers, such as sodium hyaluronate crosspolymer, are humectants. These crosspolymers strongly bind to water and are used to moisturize and plump the skin.
There is a need to provide a formulation that allows resveratrol and its derivatives, azelaic acid or a salt or ester thereof, or one or more of black cumin seed oil, chaulmoogra oil, magnolia bark extract and manuka oil to be delivered to the skin over a longer period of time following a single application and/or to cross the hydrolipidic film of the epidermis.